Study On Preparation And Properties Of Nano-TiO₂ Microspheres

TiO₂ photocatalytic oxidation as a new pollution control technology,with low energy consumption,mild reaction conditions,simple operation,an area of small and no secondary pollution,etc.,which are concerned by domestic and foreign researchers.In this paper,two major problems are the main catalyst for the solar light utilization during the low and easy abscission,through the doped metal ions to expand the scope of its light response,a highly active preparation of doped nano-TiO₂ photocatalyst and its load in silica,while the insertion of plastic,which was prepared by high-strength nano-TiO₂ microspheres.Through the use of SEM,XRD,TG,UV-Vis,IR and other means of characterization of the catalyst.In addition,reactive red(K-2BP) as the target pollutants, such as of ultraviolet irradiation in the photocatalytic activity,and its repeat utilization were discussed.Powder is recycled difficultly,the use of silica gel as the carrier of this article,PEG as dispersant,the sol - gel - impregnation method(SGI) was prepared by TiO₂-silica microspheres,and compound semiconductors and ion co-doped nano-TiO₂ Modification of a prepared composite photocatalyst load La₂O₃/ZnO/TiO₂- silica(LZT-silica). Through the characterization of photocatalyst,we can see that at calcination temperature between 400℃and 600℃samples were derived from anatase,the crystalline form was incomplete at 400℃,it was the mature phase at 500℃and obvious crystallization phenomenon happened at 600℃,SEM analysis showed that the catalyst surface smooth and rich luster,XRD analysis showed that the 500℃heat treatment from catalyst is TiO₂ anatase,IR spectra showed that some of the titanium frame had entered the silica particles,combinationof the TiO₂ and the chemical bond were realized.Degradation experiments showed that photocatalytic activity of prepared samples was the highest at 500℃.Because of photocatatyst easily load shedding,In this article,TEOS and aluminum nitrate are added in the load photocatalyst at first time,high-intensity co-doped TiO₂ microspheres were prepared by orthogonal test.The results of orthogonal test show that the microspheres obtained the highest catalytic performance when Si/Ti is 100%,Al/Ti is 20%.The experimental results indicate:photocatalyst with 3 times films has the best photocatalytic properties,the photocatalytic activity decreased when the load of the catalyst more than three times.Factors affect the degradation of the catalyst are illumination time,ventilation volume,initial concentration of K-2BP and the addition of H₂O₂.